Ventilation in the Home - January 8th 2016
Q: We read and hear a lot about ventilation and how it affects the home. What do we need to know with winter here?
A: As winter is in full swing and we are inside more, closing up the windows and doors and turning on the furnace. The indoor air quality may deteriorate making the home environment uncomfortable and unhealthy. Homes today are built to keep the cool air out; all in the name of energy efficiency. As a result, we reduced heating and air conditioning costs but at the same time made it more difficult for fresh air to move into the home and stale air to move out.
If you ever see a house in the winter with sweating windows it is a sure sign of an indoor air quality issue, specifically high relative humidity in the house.
Adequate ventilation promotes a healthier home environment by circulating and renewing the air removing pollutants and excess humidity and protecting the structure of your home by removing excessive moisture.
Types of Ventilation:
When was the last time you changed the furnace filter? This should be done all year long not just in the winter especially if you have central air conditioning or continual furnace air circulation. Filter should be changed twice a year, three times a year if your circulation fan runs 24/7 twelve months a year.
You may want to consider adding a filter to your air return grille to filter the air before it enters the ductwork and furnace. These are available in a variety of sizes to fit most existing vents.
Bathroom fans and range hoods: This is a primary way of exhausting stale moist air directly to the outside. Note: Run your bathroom fan at least one hour after each shower and bath or have a Dehumidistat installed to automatically operate the bathroom exhaust..
Heat Recovery Ventilators: Heat Recovery Ventilator “HRV” or Air to Air Heat Exchanger. The HRV allows fresh air to enter while exhausting an equal amount of stale air while recovering the heat from the exhaust side and using it to warm up the cooler fresher air coming in. This is by far the most economical way of improving the indoor air quality in the house while reducing energy consumption. Air is filtered before being redistributed in the house
Attic Ventilation: For every 200 feet of attic (roof cavity) you should have 1 square foot of venting (144 square inches). After calculating the required square inches of venting 50% (half) should go into the roof or ridge the other 50% (half) into the soffit (overhang of the home).